Course content (17 lessons)

1. About This Course — Logical Organization of Computer-II — BCA II Semester Logical Organization of Computer-II (LOC-II) is the advanced half of the computer organization sequence. Where LOC-I dealt…
2. Unit 1: CPU & Register Organization, Instruction Formats — 1.1 Inside the CPU: The Register Set The CPU is built from three cooperating parts: the register set (fast storage), the ALU (computation), and the control unit (sequencing).…
3. Unit 1: Addressing Modes with Worked EA Calculations — 2.1 What Is an Addressing Mode? An addressing mode is the rule that tells the CPU how to interpret the address field of an instruction to find the operand. The Effective Address…
4. Unit 1: Instruction Cycle, Timing & Control Signals — 3.1 The Instruction Cycle Every instruction passes through the same master loop: 1. Fetch — read the instruction from memory into IR. 2. Decode — identify opcode and addressing…
5. Unit 2: Integer Representation, Signed Arithmetic & Adders — 1.1 Representing Signed Integers With n bits we can label 2ⁿ patterns. Three schemes compete for representing negatives (examples for 8 bits, value 9): Scheme +9 −9 Range (n = 8)…
6. Unit 2: Booth's Multiplication & Division Algorithms — 2.1 Why Booth's Algorithm? Naive shift-and-add multiplication adds the multiplicand once per 1-bit of the multiplier and cannot handle negative numbers directly. Booth's algorithm…
7. Unit 2: IEEE 754 Floating Point & FP Arithmetic — 3.1 Why Floating Point? Fixed-point integers cannot simultaneously hold 0.000004 and 4 × 10¹². Floating point stores a number as ± mantissa × 2^exponent — sacrificing uniform…
8. Unit 3: Control Unit — Hardwired vs Microprogrammed — 1.1 The Control Unit's Job Unit 1 ended with Boolean control functions like LOAD(AR) = T0 + T2 + D7′·I·T3. The control unit (CU) is whatever circuit generates all such signals,…
9. Unit 3: Pipelining — Speedup, Hazards & Their Cures — 2.1 The Idea: An Assembly Line for Instructions Without pipelining, instruction i+1 waits for instruction i to finish completely. Pipelining splits execution into k stages…
10. Unit 3: RISC vs CISC — Philosophy, ARM vs x86 — 3.1 Two Philosophies of Instruction Set Design CISC (Complex Instruction Set Computer) grew in the 1960s–70s when memory was tiny and expensive and compilers were weak: make…
11. Unit 4: Memory Hierarchy & the Principle of Locality — 1.1 The Problem: Fast, Large, Cheap — Pick Two Any single memory technology forces a trade-off: SRAM is fast but expensive and power-hungry; DRAM is dense but slow; disk is…
12. Unit 4: Cache Mapping, Policies & AMAT — 2.1 The Mapping Problem Cache holds a few thousand lines (blocks) ; main memory holds millions. Mapping answers: where may a given memory block live in the cache, and how do we…
13. Unit 4: Virtual Memory — Paging, TLB & Page Replacement — 3.1 Why Virtual Memory? Virtual memory gives every process the illusion of a huge, private, contiguous address space, while physical RAM holds only the currently useful pieces.…
14. Unit 5: I/O Techniques — Programmed, Interrupt-Driven & DMA — 1.1 Why I/O Needs Its Own Architecture Peripherals differ from the CPU in speed (a keyboard delivers bytes a million times slower than the CPU consumes them), data format, and…
15. Unit 5: Bus Organization, Arbitration & Standards — 2.1 Anatomy of a Bus A bus is a shared set of lines connecting CPU, memory and I/O — cheap and extensible precisely because it is shared, which then creates the two problems this…
16. Unit 5: Parallel Processing, Flynn's Taxonomy & Cache Coherence — 3.1 Why Parallelism Became Mandatory Until ~2005, performance came from higher clock rates — until power (∝ frequency × voltage²) hit the power wall , and deeper pipelines stopped…
17. PYQ: End Term May 2024

About This Course

Logical Organization of Computer-II — BCA II Semester

Logical Organization of Computer-II (LOC-II) is the advanced half of the computer organization sequence. Where LOC-I dealt with digital logic (gates, flip-flops, combinational and sequential circuits), LOC-II climbs one level up and asks: how are those circuits assembled into a working processor, memory system, and I/O subsystem? By the end you should be able to trace an instruction from fetch to write-back, hand-compute a Booth multiplication, break a memory address into tag/index/offset fields, and argue RISC vs CISC like an architect.

📚 Unit-Wise Syllabus

🗺️ How the Lessons Are Organized

Each unit is split into three focused lessons (15 in total). Every lesson follows the same discipline:

1. Concept first — what the mechanism is and why the design exists (the "why" is where advanced marks hide).
2. Worked numeric examples — binary arithmetic digit by digit, address breakdowns, step tables for Booth's algorithm and page replacement. These mirror the style of actual end-term numericals.
3. 🎯 Exam Focus — 4–6 PYQ-style questions (define / differentiate / solve) closing every lesson, so you always know what to practice.

🎓 Exam Pattern & Strategy

| Unit questions | One long que

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Frequently asked questions

Is the Logical Organization of Computer-II course really free?

Yes. The entire Logical Organization of Computer-II course on Siksha Sarovar is free to read with no account required. You can optionally sign in with Google to save your progress.

Do I get a certificate for Logical Organization of Computer-II?

Yes — finish the lessons and pass the quiz to earn a free, verifiable certificate you can share on LinkedIn or with recruiters.

Can I run code while learning?

Yes. The built-in online compiler runs C, C++, Python, Java, PHP, JavaScript, C# and SQL directly in your browser — no installation needed.